Transportation system



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| 1 1 I I 1 '1 I I I c 200 300 400 500 600 700 800 900 0 I U I l-ll/I[""l |1" l l 70 Erich Wesener INVENTOR.

A Attorney Sept." 12, 1967 E wzsEriqER 3,340,321-

' I TRANSPORTATION SYSTEM 7 I Erich Wesener IN VENTOR.

.BY g p Attorney 8 Sheets-Sheet 5 I. v N a 1! x II" v I F I N llrm Emluflu .g a m V F 8 A Erich Wesener INVENTOR.

BY I a Y 1 Attomey Sept. 12, 1967 Filed March 29, 1965 v llws E. WESENERSept, 12, 19 67 TRANSPORTATION SYSTEM 8 Sheets-Sheet 4 Filed March 29,'1965 Fig.8

Erich Wesener [NVENTOR Attorney Sept. 12, 1967 Filed March 29, 1965 8Sheets-Sheet 5 Fig.9a

Erich Wesener INVENTOR.

Attorney Sept-12,1967 E. WESENER 3,340,321

' TRANSPORTATION VSYS'IEM Filed March 29, 1965 a Sheets-Sheet ErichWesener INVENTOR.

A Home? Sept. 12, 1967 E. WESENER 3,340,821

TRANS PORTAT-I ON SYSTEM Filed March 29, 1965 s Sheets-Sheet 7 i W f L VI j W72 70 7 7 L a a o L I I f Er /ch Wes ener INVENTOR .5 S BY w A] HomUnited States Patent ABSTRACT OF THE DISCLOSURE Inter-officetransportation system with horizontal and vertical track sections alongwhich carriages are movable between several stations, each stationhaving a siding disposed along the track, the latter including at eachstation a movable section which is shiftable out of alignment with theremainder of the hook and its alignment with the siding for directing acarriage onto such siding if a magnetic test circuit determinescorrespondence between the setting of a selector on the carriage and a'code assigned to that particular station.

My present invention relates to a transportation system designed for theconveying of preferably small articles, such as letters, files, tools,medicines, books, phonograph records or the like, over limiteddistances, e.g. within the confines of an ofiice building or anindustrial plant.

An object of this invention is to provide a transportation system ofthis character which is economical in operation by reason of the factthat electrical energy is consumed only when one or more transporters,hereinafter referred to as carriages, are in motion on any of itstracks.

Another object of this invention is to provide a system of this typewhose carriages are adapted to move over horizontal, inclined orvertical tracks in a variety of directions.

A further object of this invention is to provide, along a track of atransportation system of the type referred to, one or more junctions forthe selective switching of passing carriages onto a siding or a branchline.

Still another object, allied with the preceding one, is to provide meansat such junction for automatically switching a passing carriage from athrough going track to a branch point or siding in response to thesetting of a station selector on the carriage itself whereby eachcarriage will pass all the junctions except the one designated by itsselector.

Yet a further object, allied with the one immediately preceding, is toprovide circuit means at a junction leading to a siding for deactivatinga switching mechanism responsive to the station selector whenever thesiding is occupied by the maximum number of carriages it canaccommodate.

It is also an object of my invention to provide, in a system of thistype, track-forming means designed to hold each carriage securely on itspath, even for vertical motion, yet to facilitate the manual withdrawalof insertion of individual carriages at selected locations.

According to a feature of my present invention, I provide a track formedby a pair of parallel rails which advantageously also serve for thesupply of electric current to a carriage-borne motor and which have aprofile overhanging the wheels of the carriage so as to prevent thedetachment of the carriage from its track along vertically ascending ordescending sections thereof, e.g. sections extending along an uprightwall of a room or a building. In addition, especially in the region of asteeply inclined track section, the track may also include a rack(formed, for example, from a length of bicycle chain) engageable by amotor-driven cogwheel (such as a bi- Patented Sept. 12, 1967 cycle-typesprocket) on the carriage whereby the latter will be positively advancedat least until it reaches a less steeply inclined or horizontal tracksection. On such horizontal or nearly horizontal runs, a motor-drivenfriction roller in contact with a longitudinal ledge portion of thetrack may advance the carriage in lieu of the cogwheel, the diameter ofthe roller being advantageously larger than that of the cogwheel so thatthe carriage will travel at a higher speed under these conditions. Moreparticularly, each rail may have a generally C-shaped profile embracingwith clearance a pair of longitudinally spaced idler wheels on arespective side of the carriage; the center of gravity of the carriageshould be above the level of its wheel axes so that the carriage, whenin a vertical position, will tilt slightly within the limits of theC-profile whereby the upper wheels (i.e. the front wheels of anascending carriage) will come to rest against the overhanking flangeportion of the profile. The friction roller, if positioned forwardly ofthe rear wheels, will thereby be lifted off its ledge so that only thecogwheel remains effective to drive the carriage; the roller may also beseparated from the ledge by a suitable dimensioning of the cogwheel withreference to the position of the rack engaged thereby.

On the other hand, the friction roller (if the cogwheel is of the samediameter as the roller, or has been omitted entirely) may be coaxialwith, or take the place of, one of the rear wheels so as to be urgedinto firmer contact with the rail surface during upward travel.

The track may be composed of a series of rail segments interfitted byconnecting pins and holes, in the nature of the tracks of conventionalminiature railroads.

Each segment may be on the order of 1 meter in length (equaling abouttwo carriage lengths) and, if also used to conduct current to the drivemotor, may be energized over an individual series resistor andgalvanically separated from adjoining sections in order to minimize themutual interference occurring between the drive motors of closely spacedcarriages. In lieu of a common power source, each track section couldalso have its own current supply such as, for example, a 24-volt batteryconnected to be continuously recharged from the available utility mainswith the aid of conventional regulated chargers as generally used inautomotive power systems; such an arrangement affords an extra currentcapacity as needed to handle peak loads, e.g. upon a concurrent startingof several carriages.

The drive motor abroad such self-propelled carriage advantageously is ofthe direct-current type, with a constantfiux stator field preferablyproduced by a permanent magnet, whereby the direction of motion willdepend on the polarity of the energizing voltage applied to the two busbars along the track. If the armature of the motor is bridged by alow-resistance circuit, this motor will act as a generator and exert abraking action upon the carriage so that the latter may be effectivelyarrested on a selected track section by a short-circuiting of the twobus bars thereof. Fractional-horsepower motors, such as those used inautomotive windshield wipers, are satisfactory for most purposes.Naturally, more than one motor could be used on a single carriage (e.g.in tandem or on opposite ends of a common power shaft) in order toprovide additional power for driving. For downward travel, the vehiclecan be effectively slowed by connecting a preferably adjustable resistoracross the bus bars of a vertical or inclined track section.

connection between the motor and its drive shaft may include aself-locking worm-gear transmission which insures, at least in thepresence of a positively acting sprocket drive, that the carriage willnot slide down an inclined or vertical track section in the event ofpower failure. In such cases, however, it will be desirable to include areleasable coupling in series with the transmission so that the carriagemay be displaced manually upon being stopped accidentally betweenstations.

The upper part of the carriage, which is designed as a receptacle forthe goods to be transported and which may also be provided with adetachable cover, need not be rigidly supported by the carriage basecontaining the drive motor but may be suspended thereon, at a locationwell above its center of gravity, by a universal joint enablingomnidirectional swinging, or by a pivotal mounting affording tiltingabout a transverse horizontal axis, so that liquids or particulatesubstances may be transported without spillage over track portions withdifferent angles of elevation.

The switching of a carriage at a selected station or junction iseffected, in accordance with a further feature of my invention, with theaid of a movable track section which is normally aligned with adjoiningtrack portions so as to form a throughgoing track. When a test unitdisposed just ahead of a junction responds to the setting of acorrespondingly adjusted selector abroad a passing carriage, theswitching mechanism temporarily de-energizes the movable track sectionand bridges its conductors so that the carriage is arrested thereonwhile the track section is displaced into an alternate position in whichit is aligned with a stationary track section which may be a siding or aterminal of a branch line; if this branch line extends alongside themain track and is energized with relatively inverted polarity, thejunction will operate as a reversing point allowing the carriage toreturn in the direction from which it came (eg after having been loadedor unloaded along the route). It is, however, also possible to align aterminal track section with an incoming track portion, whereby carriageswhose selectors do not trigger the test unit will continue onto thesiding, and to make a track by a displacement of the movable tracksection. Such an arrangement is particularly suitable for a simpleshuttle-train system with a track forming a forward run and a return runbetween two terminals.

Advantageously, the movable track section is shiftable parallel toitself, preferably in a horizontal plane, so as not to develop anylinear component of acceleration tending to dislodge the stationarycarriage thereon. When the alternate position has been reached, thecircuit reconnects power to this track section so that the carriagemoves onto the adjoining receiving section. If the latter is a siding oflimited length, contacts may be provided for deactivating the test unitas soon as the maximum number of carriages have been stationed thereonwhereby further carriages will bypass this station even when theirselectors are set in accordance with the code of that station; this willprevent the accumulation of messages or goods at a temporarilyoverloaded location. Furthermore, in a system in which carriages mayfollow one another with relatively small headway, a fixed section oftrack immediately preceding the movable section may be temporarilyshort-circuited when the movable section is out of its normal positionwhereby succeeding carriages are arrested upon approaching the gap inthe throughgoing track. On the other hand, a terminal track section at asiding or a final station may be maintained de-energized andopen-circuited so that a first carriage rolling by inertia onto thatsection, will short-circuit it for the next carriage so as to preventcollision or to soften its impact.

The selector on a carriage of a system according to this invention, inconformity with another feature thereof, is advantageously constitutedby a plurality of permanently magnetized elements including one fixedmagnet and one or more adjustable magnets whose position with referenceto that of the fixed magnet spells out the code of its destination. Withthree adjustable magnets of ten positions each, for example, up -to 1000different destinations may be selected. The magnetic elements may besimple bar magnets, held in position by resilient clips (e.g. bronzesprings) or by short steel plates acting as armatures therefor; theycould, however, also be constituted by selectively magnetized portionsof, say, a magnetic tape pasted onto a side of the carriage body. In alarge building (e.g. a hospital) having a multiplicity of receivingstations distributed over a number of floors, it is possible to use oneadjustable magnet as a preselector for the floor on which the carriageis to be branched off a generally vertical track, the junction at thefloor level being then equipped with a test unit responding only to theposition of this one magnet. A second magnet, together with the first,may then identify a corridor on that floor, with the combination of allthree magnets denoting the ultimate location along the selectedcorridor. The test units will, in any event, include as manymagnetically displaceable contacts as there are selector magnets towhich they are designed to respond, the relative position of thesecontacts corresponding to the particular code of the unit so that anoperating circuit is completed only when all the contacts aresimultaneously attracted by the magnets of a passing carriage.

The above and other features of my invention will become more readilyapparent from the following detailed description, reference being madeto the accompanying drawing in which:

FIG. 1 is a fragmentary cross-sectional view of a carriage forming partof a transportation system according to the invention;

FIG. 2 is a side-elevational view of the carriage shown in FIG. 1;

FIG. 3 is a view similar to FIG. 1, showing a modified carriage;

FIG. 4 is a perspective view of part of a track, including a switchingstation, for a carriage as shown in FIG. 3;

FIG. 5 is a side-elevational view of a portion of modified track with aplurality of carriages thereon;

FIG. 5a is a cross-sectional view of the track shown in FIG. 5;

FIG. 6 is a plan view of a portion of track of the general typeillustrated in FIG. 4, including a switching station;

FIG. 7 is a view similar to FIG. 6, showing certain modifications;

FIG. 8 is a perspective view generally similar to FIG. 4, showing partof the track of FIG. 7 including the switching station;

FIG. 9 is 'a side-elevational of the track shown in FIGS. 6-8;

FIG. 9a is a cross-sectional view of the track shown in FIG. 9;

FIG. 10 is a perspective view of a track segment incorporated in thesystem of FIG. 9;

FIG. 11 is a bottom view of still another carriage adapted to be used ina system according to my invention;

FIG. 12 is an end view (parts broken away) of the carriage illustratedin FIG. 11;

FIG. 13 is a side-elevational view of the carriage shown in FIGS. 11 and12; and

FIG. 14 is a circuit diagram of the switching mech anism at a trackjunction similar to those illustrated in FIGS. 4 and 8.

In FIGS. 1 and 2 I have shown a carriage comprising a container 1 forgoods to be transported, this container being supported on a base 2 andbeing preferably removable therefrom. Base 2 contains a driving unit,here shown to comprise a cogwheel 3 driven by an electric motor 4 andmeshing with a rack 5 forming part of a track for the carriage. Frontand rear wheels 6 are freely rotatable on respective shafts, includingthe shaft of motor 4 in the case of one of the rear wheels, and areprovided with guide flanges 6a serving to center them on the lowerflanges of a pair of rails 8 of generally C-shaped profile, these railsbeing in turn supported by a U-shaped bed 7 of insulating (e.g.extruded) material such as hard polyvinylchloride. The rails 8, made forexample of brass or aluminum, may also act as bus bars for supplyingelectric current to the motor 4 via two of the wheels 6, this motorbeing advantageously of the aforedescribed permanent magnet type. Motor4 may be resiliently supported with base 2 by elastic mounting bolts notshown. Rack 5 is imbedded on three sides in a strip 9 of plasticmaterial, e.g. soft polyvinylchloride, designed to supress noise; thisrack may be constituted by a length of-chain of the type conventionallyused in bicycles. The left-hand rollers 6 (as viewed in FIG. 1) may beinvariably displaceable, against the force of a spring 100, tofacilitate removal of the carriage from the system anywhere along thetrack 7, 8.

As illustrated in FIG. 2 carriage portion 1 is equipped with adestination selector constituted by three independently adjustable barmagnets 10 and a fixed reference magnet 11, all of the permanent type.The positioning of the adjustable magnets 10 constitutes a 3-digit codenumber, as read on corresponding scales A, B and C. Differentreceptacles 1, adapted to be remova-bly mounted on any carriage case 2,may thus have their selector magnets 10 preset for differentdestinations; these receptacles may be designed, for example, toaccommodate special tools, spare parts etc. destined for the particularstations selected thereon.

In FIG. 3 I have shown a somewhat modified carriage, again comprising anupper portion 1a adapted to carry the goods and a lower portion 2acontaining at least one drive motor 4a. The shaft of this motor haskeyed to it the aforedescribed cogwheel 3, meshing with a chain 5, and afriction roller 12 riding on a preferably rough-surfaced ledge 32 atopone of the flanges of the U-shaped dielectric bed 7a. The opposite ledge32' supports an idler roller 12a, of smaller diameter, freely rotatableon its shaft. Two pairs of wheels 13 (only one pair shown) are rotatablymounted on a bracket 2' depending from carriage base 2a and bear frombelow upon the upper flanges of two generally C-shaped rails 14 whichare supported by the bed 7a and again serve as energizing conductors forthe motor. Chain 5'is mounted on the upper surface of one of the rails14.

The rollers 13 may be outwardly biased, by suitable means such as thespring 100 of FIG. 1 in order to make conductive contact with the webportions of bus bars 14 at locations where the upper flanges and partsof the webs of these bus bars are broken away (as illustrated insubsequent figures) to provide clearance for the removal of the carriagefrom the track or for the insertion of another carriage.

In FIG. 4 I have shown a switching station with a plurality of tracksections each generally similar to the track section 7a, 14 illustratedin FIG. 3 except that sheetmetal strips 18 rise from the insulating bedto form both a channel for the wheels 13 and a ledge for the roller 12of FIG. 3. Thus, the track sections seen in FIG. 4 are intended forhorizontal travel, the sprocket chain 5 having been omitted, whereas thetrack section of FIG. 3 is primarily designed for vertical movement. Twofixed sections 7a, 70 in FIG. 4 part of a throughgoing track normallycompleted by a laterally shiftable track section 7b supported ontransverse rails -15. A further track section 19, disposed alongsidesection 7c, forms a siding for carriages to be switched out of track 7a,70 by a shifting of section 7b into alignment with section 19.

A test unit, diagrammatically illustrated at 16, is disposed alongsidetrack section 7a just ahead of shiftable track section 7b and isequipped with a series of contacts 17 and 17', respectively operable bythe magnets 10 and 11 (FIG. 2) of a passage carriage; it is assumed inthis 6 case that the magnets are disposed on the lefthand side of thecarriage as seen in the direction of travel. The contacts 17 and 17'advantageously comprise sensitive ferromagnetic reeds in sealed glassenvelopes containing a protective gas, as is well known per se. Testunit 16 monitors the passing carriages and, upon detecting an array ofselector magnets corresponding to its own code as determined by thesetting of contacts 17 and 17, operates a switching circuit (describedhereinafter with reference to FIG. 14) which short-circuits the bus bars18' of section 7b to arrest the carriage on that section, displaces thelatter into its alternate position aligned with section 19, thenre-energizes the bus bars 18' of section 71) to operate the motor of thecarriage whereby the latter is driven onto the section 19, and returnssection 7b to its normal position in the throughgoing trackpreparatorily to the passage of further carriages. While section 7b isin its off-normal position, the switching circuit may also bridge theconductors 18 of section 7a to prevent any oncoming carriages fromadvancing beyond monitory device 16.

If the conductors 18, 18' are energized from a lowvoltage source (e.g.of 24 v), special insulation will not be needed to protect the operatorsbut may be provided, if desired, to prevent accidental short circuits.

The track shown in FIG. 5 is of the monorail type and, as seen in FIG.5a, consists of sections of substantially triangular profile whose crestis engagea'ble by a drive roller 101 of a carriage 20 and whoseunderside is in contact with rollers 102 which are journaled on lateralflanges 20' straddling the track. Roller 102 also may serve as currentcollectors by contacting respective bus bars on the lower track surface.The roller 101 may again be replaced or supplemented by a cogwheel, inwhich case the crest of the track may be suitably indented to form arack. Straight track sections 21 are interconnected by curved sections23 and are provided with cleats 22 by which they may be attached to thefloor or the wall of a building so as to define a partly horizontal andpartly vertical transport path.

In FIG. 6 I have shown a horizontal length of track including a straightand fixed track section 35 generally similar to the section 7a of FIG.3, a laterally shiftable track section 25, another fixed track section31 and a siding 30 alongside section 31; in the illustrated normalposition of section 25, the latter bridges sections 25 and 31 to form athroughgoing track as described for movable section 7b and fixedsections 7a, 70 of FIG. 4. Curved sections 33 and a further straightsection 35' extend the track beyond section 31. FIG. 6 also illustratespart of the mechanism for laterally shifting the track section 25, thismechanism including a crank 27 which is intermittently driven by a motor26 (as more fully described hereinafter with reference to FIG. 14) andbears at its free end a swiveling block 28 slidable guided in a groove29 on the base of section 25.

In FIG. 6 the test unit 16 is shown fixedly positioned alongside tracksection 35 just ahead of section 25. In FIG. 7, on the other hand, asimilar test unit 16a has been mounted on the base of movable tracksection 25 so as to be displaceable therewith. Also shown in FIG. 7 is acontact 36 of a normally open switch adapted to be closed by theunderside of a carriage 38 rolling from section 25 onto siding 30; thisswitch serves to start the return swing of crank 27 and, if held closedby a carriage on siding 30, deactivates the test unit 1 6a so thatsection 25 will remain in its normal position regardless of thedestination codes of further carriages moving past. At 41 there is shownan abutment designed to prevent shunted-out carriages from rolling offthe end of siding 30.

The conductive rails 14 of track sections 30 and 31 are shown partly cutaway at 132 so as to disengage the wheels 37 of a carriage 38 which canthus be manually lifted from the siding 30 and subsequently, e.g. afterreloading and/ or a readjustment of its destination selector, can beredeposited 0n track section 31 for continuation of its journey. Suchpartial cutaway, limited to the overhanging reel portions, is alsoillustrated in FIG. 4 for the track sections 70 and 19'. Similarindentations, permitting disengagement of the rollers 102, may of coursealso be provided at selected locations of the monorail track of FIG. 5.

The cutouts 132 of FIGS. 6 and 7 are shown symmetrically disposed so asto permit the insertion of a carriage 38 with either a forward or areverse orientation. Where this is undesirable, the relative position ofthe wheels 37 or other projections on opposite sides of the carriage maybe made difierent and the cutouts may be correspondingly altered so asto enable insertion with a single orientation only. For the same purposeit is possible, e.g. in the case of a monorail track as shown in FIGS.and 5a, to position a pair of bus bars at different distances from aguide rail so that contact with currentcollecting rollers of wheels willbe made only if the carriage is placed on the rail with a givenorientation.

In FIG. 8 the several track sections illustrated in FIG. 7 are shownsupported by posts 39 on the floor of a building alongside a wallthereof. A box 39 forms a slidable support for movable track section 25and accommodates the driving mechanism 26, 27 therefor. A monitoringlamp 40 visually indicates the operative condition of the system.

The horizontal track sections 31, seen in cross-section in FIG. 9a, areshown in FIG. 9 joined to curved sections 43 which lead to verticaltrack sections 45 that are substantially identical with sections 31except for the addition of a rack as described in conjunction with FIGS.1 and 3. With the aid of this rack, the carriages 38 propel themselvesupwardly as indicated by the arrow 44. The construction of such avertical track section 45 is best illustrated in FIG. which shows aninsulating bed 46 supporting conductive rails 47, of C-shaped profile,with webs 51, lower and upper flanges 48 and 50, and depending strips 49integral with each rail joined to the bed 46 by adhesive bonding and/ orother fastening means. A chain 54, forming the aforementioned rack, isclamped in a plastic strip 53 of generally U -shaped cross-sectionsecured to the bed 46.

One of the sections 45 could also be twisted helically about itslongitudinal axis, e.g. over an angle of 90, to permit the verticalportion of the track of FIG. 9 to be extended into a further horizontalrun oriented perpendicularly or at some other angle with reference tothe lower horizontal run constituted by sections 31. Naturally, it isalso possible to use several sections 45 of lesser twist adding up tothe desired overall twist angle of, say, 90.

FIG. 10 also shows holes 52 formed at one end of bed 46 to receivecomplementary pins, not shown, on a proximal face of an adjacent tracksection whereby these sections may be detachably interconnected, with orwithout conductive contact between their respective rails 47. This modeof connection, of course, can also be used with the various types ofother track sections described above.

If it is necessary to provide clearances for the reinsertion ofcarriages along vertical or steeply ascending track sections, theexcised flange portions of the rails are preferably left in place toguard against spontaneous disengagement of the carriages but aremanually swingable, e.g. by suitable toggle levels, acting against theforces of restoring springs into a retracted position in which they nolonger overhang the carriage wheels.

In FIGS. 11-13 I have shown a modified carriage 61 having a base portion67, a detachable receptacle portion 62 and a removable lid 68. A DCmotor 64 in base 67 again drives, by its output shaft, a cogwheel 65 anda roller 66, the latter being advantageously coated with a suitablyhigh-friction material for engagement with a surface 58 of a generallyU-shaped track body 55 of, for example, extruded plastic material. Trackbody 55 is formed near the edges of its base portion with twolongitudinal grooves receiving a pair of metal rails 56 which are shownhollowed out at 57 to accommodate projecting terminal pins for thepurpose of conductivity and/or mechanically interconnecting the rails ofadjacent track sections. In view of the diiferent thermal coefficientsof expansion of the plastic material of track body 55 and the metal ofrails 57, this track body may be formed at longitudinally spacedlocations with lateral incisions (not shown) enabling dimensionalchanges of the rail support without undue deformation of the railsthemselves. Idler rollers, 63, again serving as carriage wheels and ascurrent collectors for motor 64, ride on the rails 57. Track body 55 isfurther formed with a longitudinal ridge 59 straddled with a dovetailfit by a plastic strip 60, e.g. of soft polyvinylchloride, whichembraces a chain 60 cooperating with cogwheel 65.

Naturally, the rails 56 shown in FIG. 12 could also be longitudinallyinserted into the upper part of the flanges of track body 55, i.e. abovethe rollers 63, whereupon the assembly may be so dimensioned that therollers 66 and/ or the cogwheel 65 lift these rollers by a fewmillimeters above the base of track portion 55 to contact the overlyingconductors, in the manner illustrated for the rollers 13 in FIG. 3.

As shown in FIGS. 11 and 13, the destination selector provided on theremovable upper carriage portion 62 includes a set of three adjustablebar magnets 71 selectively positioned along respective bars 70 in orderto define a three-digit code as described in conjunction with magnets 10of FIG. 2. A stationary magnet 72 (seen in FIG. 11) corresponding tomagnet 11 of FIG. 2, is attachable to the carriage by clips 69. Similarclips 72' are provided at fixed locations just above the bars 70 toreceive additional magnets, not shown, whereby a homing code for thecarriage is spelled out which insures that the carriage will always havereturn to a designated originating station after having been returned tothe track upon reaching its selected destination or after havingbypassed this destination on account of an overload condition at thelatter.

Reference will now be made to FIG. 14 for a description of a circuitarrangement designed to perform the various operations previouslydescribed in conjunction with a switching station of the typeillustrated in FIGS. 4 and 6-8.

In FIG. 14 a section of incoming track is constituted by a set of rails141, 142, 143, rail 142 being permanently grounded at 76 whereas rail141 is permanently connected to a source of negative potential. Thisnegative potential is also applied, via a fuse 164, to a live bus barcomposed of conductors 167, 168, 169, 170, 171, 172 and 83. Rail 143 isnormally connected to this bus bar by a reversing contact 81 of asolenoid 160 whose winding lies in series with a make contact 78 of aholding relay 159 between ground 76 and conductor 167.

The movable track section of the switching station comprises a pair ofrails 144, 145 interconnected by a plate which is transverselydisplaceable over auxiliary rails 150 under the control of a motor 153;the motor drives a crank 154 whose ,free end carries a roller 155slidably received in a groove 150 (shown partly in phantom lines) on theunderside of plate 150, in the manner described with reference to crank27, slider 28 and groove 29 of FIG. 7. Another fixed track section iscomposed of a permanently grounded rail 149 and a rail 148 permanentlyconnected to section 171 of the negative bus bar. A further fixed tracksection, similar to siding 30 of FIGS. 68, consists of a groundedconductor 147 and another conductor 146 connected via leads 94 and 92 toa make contact of a switch arm 156, the latter in turn being connectedto the same negative voltage via leads 89 and 90 in series with a breakcontact 88 of motor relay 161. The winding of relay 161 is shownconnected in a circuit extending from the break contact of arm 156 vialeads 85 and 86 over a make contact 82 of solenoid 160 to ground on rail142.

Contact arm 156 is positioned in the orbital path of crank roller 155for displacement thereby as soon as the crank 154 has swung from itsillustrated starting position, in which rails 144 and 145 are alignedwith rails 143, 148 and 142, 149 through an angle of approximately 180into an alternate position in which rails 144 and 145 register withrails 146 and 147, respectively. A second contact arm 157, displaceableby the crank roller 155 as the latter approaches its normal position,has a back contact connected via a conductor 75 to the winding ofholding relay 159 which, in the normal position of arm 157, isenergizable in a circuit extending over a conductor 74 and a pluralityof test contacts 152 of a monitoring unit 151 (similar to unit 16 or 16aof FIGS. 6-8) in series as well as a lead 73 and a back contact of aswitch arm 158 to negative voltage on bus conductor 172. Switch arm 158corresponds to the arm 36 illustrated in FIGS. 7 and 8. Contacts 152 aresimultaneously closed when a corresponding array of magnets 10', 11(FIG. 2) or 71, 72 (FIGS. 11 and 13) are positioned alongside unit 151;only three such contacts have been shown for the sake of simplicityalthough four would generally be needed when the selector of a passingcarriage includes one fixed and three adjustable magnets.

FIG. 14 also shows, diagrammatically, the aforedescribed cutouts 132provided on rails 146 and 147 to facilitate removal of a carriagestationed on the siding. In addition, the circuit includes a monitoringlamp 163, similar to lamp 40 of FIG. 8; an adjustable resistor 165,inserted between the front contact of armature 88 of motor relay 161 andground at 76; and an optional reversing relay 162 having armatures 96,98 and 97, the latter normally connecting negative voltage fromconductor 170 to rail 144 by way of another armature 87 of unoperatedmotor relay 161.

The operation of the system illustrated in FIG. 14 will now bedescribed.

In the quiescent state, i.e. as long as test unit 151 does not respondto the passage of a carriage along rail sections 143, 143 bysimultaneous closure of all its contacts 152, the armature of motor 153is short-circuited by negative potential on input leads 84 and 89 sothat this motor, assumed to be of the aforedescribed constant-flux type,fixedly maintains its crank 154 in the illustrated position in whichrails 144, 145 complete a throughgoing track. If, now, unit 151 respondsto an appropriately preset selector on a passing carriage, theconcurrent closure of all contacts 152 energizes holding relay 159 whichlocks independently of these contacts over its armature 77 and attractsits armature 78 to energize the solenoid 160. The solenoid thereuponreverses its armature 81 and removes negative operating potential fromrail 143 which the carriage has just left; this rail is now connected toground at 76 so that rails 142, 143 are eifectively bridged toshortcircuit the armatures of the drive motors of succeeding carriagesthat may alight on this track section. It will be understood that thelength of rail 143 should be chosen suflicient to accommodate themaximum number of carriages expected during an operating cycle ofswitching motor 153.

Solenoid 160 also attracts its armature 82 to energize motor relay 161with the following result: armature 88 of relay 161 removes negativevoltage from input lead 89 of motor 153 and connects this lead insteadto ground at 76 via resistor 165 which has been suitably adjusted tocontrol the operating speed of the motor. Crank 154 starts to cam theplate 150' with its shiftable rails 144, 145 out of their normalposition and into their alternate position in line with rails 146 and147; armature 87 disconnects rail 144 from negative voltage on conductor170 and connects it instead to ground 76 so that both rails 144, 145 arenow at the same potential and the carriage positioned thereon is sharplybraked by a short-circuiting of its motor armature.

Upon completing a swing through 180 or through a slightly differentangle (as determined by the preferably adjustable mounting of contactarm 156 with reference to crank 154) in which rails 144 and 145 alignwith rails 146 and 147, arm 156 is tripped to break the operatingcircuit of relay 161 whose armature 88 once more shortcircuits the inputterminals of motor 153 whereby the latter is rapidly brought to a stop.Ann 156 now applies negative potential from conductor 83 via leads 92and 94 to rail 146. Shortly thereafter, the return of armature 87 ofmotor relay 161 to normal restores negative voltage from conductor 170to rail 144 so that both track sections 144, 145 and 146, 147 are nowenergized and the shunted carriage rolls from section 144, 145 ontosiding 146, 147. In doing so, it depresses the switch arm 158 whichconnects negative voltage from conductor 172 via a lead 93 and lead 86in series with closed solenoid armature 82 to the winding of motor relay161 so as to reoperate the latter. Crank 154 begins to move again andpromptly releases the switch arm 156 so that this arm via its breakcontact maintains relay 161 opera-ted independently of contact 158 whichreturns to normal as soon as the carriage continues toward the far endof siding 147, 148. The momentary deactivation of the test circuitthrough the contacts 152 of unit 151 by the reversal of contact 158 iswithout practical significance at this time since track section 142, 143is still short-circuited so that no carriages will roll past the testunit 151.

As soon as crank arm 154 passes the location of switc arm 157, itdisplaces the latter to open the holding circuit of relay 159 whichreleases and at armature 78 de-energizes the solenoid 160. Solenoidarmature 81 thereupon reconnects negative voltage to rail 143 wherebynormal through traflic will resume, the circuit of motor relay 161 beingagain broken by solenoid armature 82. It will be apparent that themounting of switch arm 157, too, should be suitably chosen to arrest therail section 144, 145 in a position of exact alignment with sections142, 143 and 148, 149.

If a second carriage with the proper code designation triggers the unit151 so as to be subsequently shifted onto siding 146, 147, it will findthe rails 146, 147 bridged by the motor armature of the first carriageso that, as soon as negative potential has been removed from rail 146 bythe restoration of switch arm 156, its own motor will a as a generatorand will exert a braking effect upon the second carriage while the firstcarriage will have its motor energized by the current so generated, withthe result that the first carriage begins to roll slightly beyond theposition last reached whereas the second carriage will slow down so thata collision is avoided or at least reduced to a slight impact.

When the maximum number of carriages have reached the siding 146, 147,the last of them holds the switch contact 158 permanently depressed sothat test unit 151 remains deactivated and further carriages will bypassthe station without any operation of shifting motor 153.

The reversing relay 162 may be connected in circuit when it is desiredto discharge a shunted-out carriage from rail section 144, 145 in theopposite direction, i.e. to the left in FIG. 14, over a branch track146', 147' facing the siding 146, 147. For this purpose there may beprovided a switch arm 99 adapted to be tripped mechanically ormagnetically by a special projection or a special selector magnet on acarriage which is to be routed over this additional track 146', 147'.When the relay 162 is so connected in circuit, reversal of switch arm156 energizes this relay so that its armature 96 connect rail 145 tolead 192, in parallel with rail 146, while its armature 97 grounds theother movable rail 144. The polarity of energization of rail 144 and145, occurring upon the tripping of arm 156 by crank 154, is thusreversed and corresponds to that permanently applied to the rails 146,147' leading to the home terminal of the carriage or to some otherdestination.

Relay 162, upon operating, locks to conductor 92, independently ofcontact 99, over an armature 98. A switch arm 158', disposed along tracksection 146', 147', for operation by a carriage passing thereover,reoperates the relay 161 in the manner heretofore described withreference to switch arm 158 to start the return stroke of crank 154.This crank, if desired, may also be provided with a conventional detent(e.g. a spring-loaded ball) designed to index it in either of its twoalternate positions.

Lamp 163 lights in an obvious circuit, including a lead 91, wheneverpower is applied to the system.

I claim:

1. In a transportation system, in combination:

a rail-forming track comprising a pair of longitudinally extendingparallel conductors;

at least one carriage displaceable along said track, said carriageincluding a motor and contact means engageable with said conductors forenergizing said motor;

branching means on said track including a movable track section having anormal position and an on?- normal position, said track furtherincluding a first fixed section leading to said movable section, asecond fixed section continuing beyond said movable section and alignedtherewith in said normal position thereof, and a third fixed sectionaligned with said movable section in said off-normal position thereof;

mechanism for displacing said movable section between said normal andsaid off-normal position;

control means for selectively actuating said mechanism during presenceof said carriage on said movable section;

and switch means responsive to said control means for tie-energizingsaid movable section in its normal position immediately prior tooperation of said mechanism and for re-energizing said movable sectionupon arrival thereof in its off-normal position whereby said carriage isactuated to move onto said third fixed section.

2. The combination defined in claim 1 wherein said control meanscomprises selector means on said carriage and test means adjacent theentrance end of said movable section positioned to respond to apredetermined setting of said selector means upon passing of saidcarriage onto said movable section.

3. The combination defined in claim 2 wherein said selector meanscomprises a plurality of magnetic elements on a side of said carriage,said test means including a plurality of contacts respectivelyactuatable by said magnetic means.

4. The combination defined in claim 1 wherein said mechanism comprises arotatable crank, said movable section being coupled with said crank fortransverse displacement parallel to itself.

5. In a transportation system, in combination:

a track divided into a plurality of rail sections each comprising a pairof longitudinally extending parallel conductors;

a plurality of carriages displaceable along said track,

each carriage including a motor with a direct-current armature and aconstant-fiux stator and contact means engageable with said conductorsfor energizing said motor;

a plurality of junctions along said track each including a movable railsection having a normal position and an off-normal position, a firstfixed rail section leading to said movable section, a second fixed railsection continuing beyond said movable section and aligned therewith insaid normal position thereof, and a third fixed rail section alignedwith said movable rail section in said off-normal position thereof;

mechanism at each junction for displacing said movable rail sectionbetween said normal and said offnormal position;

selector means on each carriage distinctively positioned for identifyingone of said junctions;

test means at each junction positioned for monitoring 12 the selectormeans of passing carriages and for producing a signal upon passing of acarriage identifying the respective junction on the selector meansthereof;

control means for selectively actuating said mechanism in response tosaid signal upon arrival of the lastmentioned carriage on said movablerail section; and switch means responsive to said control means fordeenergizing said movable rail section in its normal positionimmediately prior to operation of said mechanism and for re-energizingsaid movable rail section upon arrival thereof in its olf-normalposition whereby the carriage thereon is actuated to move onto saidthird fixed rail section.

6. The combination defined in claim 5, further comprising circuit meansoperable by said switch means for bridging the conductors of said firstfixed rail section upon displacement of said movable rail section fromits normal position, thereby short-circuiting the armature of asubsequent carriage arriving on said first fixed rail section forarresting said subsequent carriage on said first fixed rail section.

7. The combination defined in claim 5 wherein said switch means includescontacts for short-circuiting said movable rail section duringdisplacement thereof by said mechanism, thereby immobilizing saidfirst-mentioned carriage on said movable rail section.

8. The combination defined in claim 5 wherein said switch means includescarriage-controlled contacts selectively operable for reversing thepolarity of energization of said movable rail section in its off-normalposition whereby the carriage thereon can be driven off in eitherdirection, at least one of said junctions further including a fourthfixed rail section aligned with said movable rail section in saidoff-normal position thereof at a location opposite said third fixed railsections.

9. The combination defined in claim 5 wherein said mechanism comprises aswitching motor with a directcurrent armature and a constant-fluxstator, said switch means including contacts responsive to arrival ofsaid movable rail section in said off-normal position forshortcircuiting the armature of said switching motor.

10. The combination defined in claim 9 wherein said mechanism furthercomprises a rotatable crank driven by said switching motor and coupledwith said movable rail section, said contacts being positioned foroperation by said crank.

11. The combination defined in claim 10 wherein said switch meansincludes further contacts at said third fixed rail section responsive topassage of a carriage thereover for re-energizing the armature of saidswitching motor, and additional contacts operable by said crank upon return of said movable rail section to said normal position for againshort-circuiting the armature of said switching motor.

12. A transportation system comprising a track divided into a pluralityof longitudinally adjoining rail sections including a substantiallyhorizontal section and a substantially vertical section, aself-propelled carriage displaceable along said track, drive means onsaid carriage including a friction roller of relatively large diameterand a cogwheel of relatively small diameter provided with a commonshaft, said track having a surface engageable by said roller forpropulsion of said carriage at relatively high speed along saidsubstantially horizontal section, wheels on said carriage positioned forcontact with said track, retaining means on said track engageable withsaid wheels for permitting limited separation of said roller from saidsurface upon movement of said carriage along said substantially verticalsection, and a rack on said substantially vertical section engageable bysaid cogwheel for movement at relatively low speed along saidsubstantially vertical section during separation of said roller fromsaid surface.

13. A transportation system as defined in claim 12 wherein said wheelsinclude front and rear wheels rotatable about respective axes, therear-wheel axis being located rearwardly of said roller, said carriagehaving its center of gravity so disposed as to tilt the carriage aboutsaid rear-wheel axis during movement along said substantially verticalsection, thereby separating said roller from said surface.

14. A transportation system as defined in claim 12 wherein said sectionsare substantially channel-shaped and have longitudinal edge portionsformed into overhanging flanges constituting said retaining means, saidfront wheels engaging said flanges during tilting of said carriage.

15. A transportation system as defined in claim 14 wherein the flangesof said horizontal section are partly cut away for enabling withdrawaland reinsertion of the 15 carriage.

16. A transportation system as defined in claim 15 wherein said carriageincludes a base portion containing said drive means and a receptacleportion mounted on said base portion.

17. A transportation system as defined in claim 16 wherein saidreceptacle portion is externally provided with destination-selectormeans including a distinctive array of permanent bar magnets disposed atdifierent levels.

18. A transportation system as defined in claim 17 wherein said barmagnets include a fixed magnet and a 14 plurality of adjustable magnetseach selectively positionable in a plurality of positions longitudinallyspaced along an outer wall surface of said receptacle portion foridentifying a selected station.

19. A transportation system as defined in claim 18 wherein said barmagnets further include a plurality of additional magnets disposed atfixed positions adjacent the levels of said adjustable magnets foridentifying a permanent home station.

References Cited UNITED STATES PATENTS 678,312 7/1901 Gilmer 104-138717,798 1/1903 Beerwald' 104-139 X 892,586 7/1908 Ferlin 105-29 X1,038,504 9/1912 Smith 104-139 1,438,266 12/1922 Schoberle 105-292,322,640 6/1943 Jackson et a1. 191-23 X 3,028,455 4/1962 Devonshire191-23 3,074,353 1/ 1963 Devonshire et al 104-88 3,158,710 11/1964Paglee 104-88 X ARTHUR L. LA POINT, Primary Examiner.

S. B. GREEN, D. F. WORTH, Assistant Examiners.

1. IN A TRANSPORTATION SYSTEM, IN COMBINATION: A RAIL-FORMING TRACKCOMPRISING A PAIR OF LONGITUDINALLY EXTENDING PARALLEL CONDUCTORS; ATLEAST ONE CARRIAGE DISPLACEABLE ALONG SAID TRACK, SAID CARRIAGEINCLUDING A MOTOR AND CONTACT MEANS ENGAGEABLE WITH SAID CONDUCTORS FORENERGIZING SAID MOTOR; BRANCHING MEANS ON SAID TRACK INCLUDING A MOVABLETRACK SECTION HAVING A NORMAL POSITION AND AN OFFNORMAL POSITION, SAIDTRACK FURTHER INCLUDING A FIRST FIXED SECTION LEADING TO SAID MOVABLESECTION, A SECOND FIXED SECTION CONTINUING BEYOND SAID MOVABLE SECTIONAND ALIGNED THEREWITH IN SAID NORMAL POSITION THEREOF, AND A THIRD FIXEDSECTION ALIGNED WITH SAID MOVABLE SECTION IN SAID OFF-NORMAL POSITIONTHEREOF; MECHANISM FOR DISPLACING SAID MOVABLE SECTION BETWEEN SAIDNORMAL AND SAID OFF-NORMAL POSITION; CONTROL MEANS FOR SELECTIVELYACTUATING SAID MECHANISM DURING PRESENCE OF SAID CARRIAGE ON SAIDMOVABLE SECTION; AND SWITCH MEANS RESPONSIVE TO SAID CONTROL MEANS FORDE-ENERGIZING SAID MOVABLE SECTION IN ITS NORMAL POSITION IMMEDIATELYPRIOR TO OPERATION OF SAID MECHANISM AND FOR RE-ENERGIZING SAID MOVABLESECTION UPON ARRIVAL THEREOF IN ITS OFF-NORMAL POSITION WHEREBY SAIDCARRIAGE IS ACTUATED TO MOVE ONTO SAID THIRD FIXED SECTION.